Power distribution unit

Abstract

The invention relates to a power distribution unit having at least one first electrical connection region and at least one second electrical connection region, a first electrical contact element of the first electrical connection region and a second electrical contact element of the second electrical connection region being electrically connectable and disconnected via at least one movable third electrical contact element, the third electrical contact element is biased in a switching arrangement by means of at least one elastic element and can be actuated in at least one different switching arrangement by means of an actuator unit having at least one actuator and at least one switching shaft which can be moved by means of the actuator, and on the basis of the actuated switch setting, the third electrical contact element is in a biased switch setting or the third electrical contact element is moved in at least one different switch setting against the spring force of the elastic element, the switch shaft drives the switch wheel via the drive wheel, the switch wheel-drive wheel combination forming a step gear.

Description

Technical Field

[0001] The present invention relates to a power distribution unit having at least two electrical connection regions, specifically at least one first electrical connection region and at least one second electrical connection region, wherein the first electrical connection region has at least one fixed first electrical contact element, and the second electrical connection region has at least one fixed second electrical contact element, wherein the first and second electrical contact elements are electrically connected and disconnected via at least one movable third electrical contact element, wherein the third electrical contact element is biased in a switching configuration via at least one elastic element and is actuated in at least one different switching configuration via an actuator unit, wherein the actuator unit has at least one actuator and at least one mechanical engagement portion with a switch shaft, the mechanical engagement portion being movable via the actuator, and, based on the actuated switching configuration, the third electrical contact element is either placed in a biased switching configuration or moved against the spring force of the elastic element to be in at least one different switching configuration. Background Technology

[0002] The power distribution unit for motor vehicles, especially for hybrid or electric motor vehicles, has, in addition to the fuse unit, voltage measurement system, and current measurement system, a switching device that prevents or allows current to flow through the vehicle's electrical circuits.

[0003] Typically, these switching devices consist of at least three relays, and depending on the design, at least two high-current relays and one pre-charge relay are installed. In some cases, additional relays are also installed for opening and closing the drive unit, DC charging contacts, battery pack switching, and for other functions.

[0004] Each of the relays used includes contacts and actuators, which are enabled by the corresponding output stage of the control device and monitored via specific circuitry.

[0005] Besides the high cost, using multiple individual relays and actuators increases the space requirements and weight. Furthermore, relays typically have two high-current connections that can only be passively cooled via attached busbars. This negatively impacts the installation space and weight of the contact technology. The requirements for current carrying capacity, as well as closing and opening speeds, also necessitate actuator adaptation. This negatively affects overall mass, volume, and energy efficiency. Additionally, it necessitates complex control and monitoring systems for each individual relay to identify or prevent failures. All these disadvantages combined lead to the desire for an improved switching device suitable for use in the power distribution units of battery electric vehicles.

[0006] The high-voltage (HV) relays used are typically identical in structure, and each relay includes contacts and an actuator. They are enabled by a corresponding output stage of the control device and monitored via specific circuitry. Each of these relays incorporates the necessary integration technology to interrupt current flow even under load.

[0007] A switching device is known from the previously unpublished patent DE 10 2023 209 219. This switching device has a camshaft or crankshaft as a central actuating element for actuating contacts. Depending on the number of switches, the actuating shaft has different switching positions. Since it is a spring-loaded unit, it is important that the contacts and shaft remain in defined switching positions. The springs are susceptible to external environmental influences such as vibrations and acceleration peaks, and therefore an electromechanical actuation design for the camshaft or crankshaft is necessary to ensure that the individual switches remain firmly engaged or open in their respective switching positions.

[0008] Because switching needs to be performed under load in certain situations, the switch contacts must open or close within a limited time; otherwise, excessive electric arcing will occur at the contacts. This arcing can lead to component wear.

[0009] The object of the present invention is to provide an improved electromechanical switching device in which the switch is securely and simply connected. Summary of the Invention

[0010] This objective is achieved by a power distribution unit having at least two electrical connection regions, specifically at least one first electrical connection region and at least one second electrical connection region. The first electrical connection region has at least one fixed first electrical contact element, and the second electrical connection region has at least one fixed second electrical contact element. The first and second electrical contact elements are electrically connected and disconnected via at least one movable third electrical contact element. This third electrical contact element is biased in a switching configuration via at least one elastic element and actuated in at least one different switching configuration via an actuator unit. The actuator unit has at least one actuator and at least one mechanical engagement with a switch shaft, the mechanical engagement being movable via the actuator. Based on the actuated switching configuration, the third electrical contact element is either placed in a biased switching configuration or moved against the spring force of the elastic element to be in at least one different switching configuration. The actuator unit drives a switch wheel via a drive wheel, and the switch wheel-switch shaft combination constitutes a stepping gear.

[0011] This solution allows the switch shaft to rotate a defined angle along the actuation path. Rotation can be performed in variable steps of 30°, 60°, and 90°, depending on the geometry and switch settings required. The solution also ensures the camshaft remains in a defined position. The additional holding force generated by the electric actuator can be omitted.

[0012] The outer contour of the switch wheel has a concave blade surface between the groove and the blade tip.

[0013] The grooves are distributed at equal or unequal intervals and extend radially toward the pivot point of the switch wheel.

[0014] The drive wheel has a journal for engaging in a groove in the switch wheel, and a convex profile for supporting the concave blade surface of the switch wheel.

[0015] The cam on the switch shaft presses against the spring force of the elastic element to press the third contact element.

[0016] The elastic element is a compression spring, preferably a leaf spring or a coil spring.

[0017] By actuating the power distribution unit, the journal engages in the groove of the switch wheel by rotating the drive wheel, and the switch wheel rotates further, wherein, upon further rotation, the journal slides out of the groove, and the switch wheel rotates back to the starting position, in which the switch wheel is supported on the drive wheel by a convex surface. Attached Figure Description

[0018] Figure 1 This illustrates a power distribution unit in the prior art;

[0019] Figure 2 The cross-section along line A~A is shown;

[0020] Figure 3 An embodiment of the circuit according to the present invention is shown;

[0021] Figure 4 The switching sequence of this embodiment is shown. Detailed Implementation

[0022] The present invention is based on a power distribution unit that will use Figure 1 Described using examples.

[0023] exist Figure 1 The image depicts a variant of one embodiment of the electromechanical switching device 1. The electromechanical switching device 1 has a first electrical connection region 2 and a second electrical connection region 3. The first electrical connection region 2 and the second electrical connection region 3 are arranged adjacent to each other on a cooling unit 13 and are located in a first structural plane X.

[0024] The first electrical connection region 2 has a plurality of fixed first electrical contact elements 4a to 4g, specifically seven first electrical contact elements 4a to 4g.

[0025] The second electrical connection region 3 has a plurality of fixed second electrical contact elements 5a to 5g, specifically seven second electrical contact elements 5a to 5g.

[0026] The corresponding first electrical contact elements 4a~4g of the first electrical connection area 2 can be connected and disconnected from the corresponding second electrical contact elements 5a~5g of the second connection area 3 via the corresponding third contact elements 6a~6g.

[0027] Therefore, each of the third contact elements 6a~6g can be controlled by the actuator unit 8 to be in two switch settings A and B, specifically the first switch setting A and the second switch setting B.

[0028] According to Figure 1 and Figure 2 In a variation of the implementation, the first switch setting A corresponds to a switch setting in which the corresponding first electrical contact element 4a~4g is electrically connected to the corresponding second electrical contact element 5a~5g via the corresponding third electrical contact element 6a~6g.

[0029] According to Figure 1 In a variation of the implementation, the second switch setting B corresponds to a switch setting in which the corresponding first electrical contact element 4a~4g is electrically disconnected from the corresponding second electrical contact element 5a~5g, such as... Figure 2 As depicted in the text.

[0030] The actuator unit 8 includes an actuator 9 and a switch shaft 10. The actuator 9 is designed as an electric motor 9a, and the switch shaft 10 has a plurality of switching elements 11, specifically seven switching elements 11. The switch shaft 10 is formed as a cam shaft 10a, and each switching element 11 of the switch shaft 10 is formed by a cam fixed to the cam shaft 10a.

[0031] In each case, a switching element 11 of the switching shaft 10 is functionally assigned to a third electrical contact element 6a~6g.

[0032] The switch shaft 10 is also arranged in the first construction plane X and is located in the region between the first electrical connection region 2 and the second electrical connection region 3, and extends axially between the two electrical connection regions 2 and 3.

[0033] The direction indicator “axial” should be understood as the direction along or parallel to the central longitudinal axis 12 of the switch shaft 10.

[0034] The first electrical connection region 2 and the second electrical connection region 3 are partially arranged in the housing 14, and specifically, the first electrical contact element 4a~4g and the second electrical contact element 5a~5g are arranged inside the housing 14, and the connection point 20 of the corresponding electrical connection regions 2 and 3 is formed outside the housing 14.

[0035] The corresponding connection point 20 is electrically connected in each case to at least one corresponding first electrical contact element 4a~4g or second electrical contact element 5a~5g of the corresponding connection area 2, 2', 3, 3'.

[0036] The switch shaft 10 is basically mounted in the housing 14 and is designed to be rotatably driven by an electric motor 9a arranged outside the housing 14.

[0037] The third electrical contact elements 6a-6g are arranged on the inner wall 15 of the housing 14 via two elastic elements 7 in each case, located in the second construction plane Y. In the present case, the elastic elements 7 are specifically compression springs 7a, and specifically, in each case, the third electrical contact elements 6a-6g are arranged substantially parallel to the two electrical connection regions 2, 3 and their corresponding electrical contact elements 4a-4g, 5a-5g.

[0038] The second construction plane Y corresponds to a spatial plane that is parallel to the first construction plane X.

[0039] The third electrical contact elements 6a-6g and the camshaft 10a are arranged such that, in each case, the cam of the camshaft 10a can control the third electrical contact elements 6a-6g to be in one of two switching settings, A and B.

[0040] In the first switch configuration A, the corresponding first electrical contact elements 4a~4g are electrically connected to the corresponding second electrical contact elements 5a~5g via the corresponding third electrical contact elements 6a~6g. Figure 1 and Figure 2 In the embodiment variant described herein, it is achieved in such a way that the corresponding third contact elements 6a~6g are radially biased along the direction of the corresponding first electrical contact elements 4a~4g and the corresponding second electrical contact elements 5a~5g assigned to them via spring 7a, thus being in a closed configuration.

[0041] In the second switch setting B, see Figure 2 The corresponding third contact element 6a~6g is moved radially against the spring force of the spring 7a along the inner wall 15 of the housing 14 by the cam assigned to the corresponding third contact element via the camshaft 10a, so that the corresponding first electrical contact element 4a~4g is disconnected from the corresponding second electrical contact element 5a~5g, thereby realizing the opening setting.

[0042] In the first switch setting A, the corresponding first electrical contact elements 4a~4g are electrically connected to the corresponding second electrical contact elements 5a~5g via the corresponding third electrical contact elements 6a~6g.

[0043] According to the present invention, as follows Figure 3 and Figure 4 In one embodiment, actuator unit 8 includes actuator 9, which may be designed as a DC motor, brushless DC (BLDC) motor, stepper motor or other rotating machine.

[0044] The actuator unit 8 also includes interconnecting gears, which can be designed as spur gears, planetary gears, or other transmission gears, and achieve gear reduction of the electric motor of the actuator 9. Downstream of this gear is a stepping gear that constitutes an intermittent motion device.

[0045] Figure 3 A view of the end face of the power distribution unit is shown, in which only a portion of the actuator unit 8 is depicted.

[0046] Actuator unit 8 includes a drive wheel 30, which is connected to actuator 9 via interconnecting gears. The drive wheel 30 is mounted in the end face region of housing 14 and rotates about axis 40. Switch shaft 10 is also mounted in the end face region of housing 14.

[0047] Figure 4 The sequence of operations is shown, but for Figure 3 A view of the rear side of the drive wheel 30.

[0048] The drive wheel 30 has a journal 31 and an edge 35 that extends radially inward relative to the axis of rotation. The edge 35 forms a convex arcuate section that engages with the switch wheel 32. Therefore, the defined switching position is fixed by using this geometry. No additional retaining force from the outside is required.

[0049] The switch wheel 32 is formed in the shape of a Maltese cross, with evenly distributed grooves 33 on its circumference. The switch wheel 32 is mounted on the switch shaft 10.

[0050] exist Figure 4 In an exemplary embodiment, four grooves 33 are offset from each other by 90 degrees and extend in the direction of the rotation axis of the switch wheel 32, thus facing the switch shaft 10. To lock the switch position, the switch wheel 32 has arcuate segmental recesses on its circumference between the grooves 33, which form concave blade surfaces 36.

[0051] The drive wheel 30 and the switch wheel 32 together form the stepping gear 46.

[0052] Figure 4 The switching process is depicted in the figure. Starting from the top, the switch wheel 32 is in such a position that the concave blade surface rests on the edge 35 of the switch wheel 32, and the journal 31 is not yet accommodated in one of the grooves of the groove 33.

[0053] When the drive wheel 30 rotates, the protruding journal 31 engages in one of the grooves 33 on the switch wheel 32.

[0054] As the drive wheel 30 continues to rotate, the journal 31 moves along one of the grooves in the groove 33, causing the switch wheel 32 to rotate by a fixed angle value, typically in integer increments of 360°. This can... Figure 4 As seen in the second image from the top, the switch wheel 32 rotates in the opposite direction to the drive wheel 30. Connecting the switch wheel 32 to the switch shaft 10 causes the switch shaft to twist, and thus causes the cam on the switch shaft to twist. The movement of the cam causes the contact elements 6a~6g to open and close.

[0055] exist Figure 4 In the third image from the top, a further rotation process can be seen, in which the switch wheel 32 rotates further and again seeks the concave blade surface 36 to be positioned opposite the edge 35 of the drive wheel 30.

[0056] Once journal 31 reaches the end of groove 33, it is released from switch wheel 32, resulting in paused or intermittent movement. The edge 35 of drive wheel is formed as a convex arc segment and engages with switch wheel, see... Figure 4 The bottom image shows the switch position. Therefore, the defined switch position is fixed using geometry. No additional holding force from the outside is required. Furthermore, the dynamics of position adjustment are improved. Actuator overshoot no longer affects the angular position of the switch shaft, as this angular position is already fixed via the engaged arc segment.

[0057] The sequence of motion remains the same for all other switch configurations, with journal 31 engaging in each case in a different groove 33 on the switch wheel. Whether the drive wheel rotates clockwise or counterclockwise is irrelevant. In fact, this allows the contacts of the electromechanical switching device to close and open discretely and repeatably.

Claims

1. A power distribution unit (1), the power distribution unit (1) having at least two electrical connection regions, specifically having at least one first electrical connection region (2, 2') and at least one second electrical connection region (3, 3'), wherein, The first electrical connection region (2, 2') has at least one fixed first electrical contact element (4a~4g), and the second electrical connection region (3, 3') has at least one fixed second electrical contact element (5a~5g). The first electrical contact element (4a~4g) and the second electrical contact element (5a~5g) can be electrically connected and disconnected via at least one movable third electrical contact element (6a~6g). The third electrical contact element (6a~6g) is biased in a switching configuration (A, B) via at least one elastic element (7) and can be actuated in at least one different switching configuration (A, B) via an actuator unit (8). The actuator unit (8) has at least one actuator (9) and at least one mechanical engagement with a switch shaft (10), the switch shaft (10) being movable via the actuator and, based on the actuated switch settings (A, B), either placing the third electrical contact element (6a~6g) in a biased switch setting (A, B) or moving the third electrical contact element (6a~6g) against the spring force of the elastic element (7) to be in at least one different switch setting (A, B), wherein the actuator unit (8) drives the switch wheel (32) via the drive wheel (30), and wherein the switch wheel (32)-drive wheel (30) combination constitutes a stepping gear (46).

2. The power distribution unit (1) according to claim 1, wherein, The outer contour of the switch wheel (32) has a concave blade surface (36) between the groove (33) and the blade tip.

3. The power distribution unit (1) according to claim 2, wherein, The grooves are distributed at equal or unequal intervals and extend radially toward the pivot point of the switch wheel (32).

4. The power distribution unit (1) according to claim 2, wherein, The drive wheel (30) has a journal (31) and a convex profile (35), the journal (31) being used to engage in the groove of the switch wheel, and the convex profile (35) being used to support the concave blade surface (36) of the switch wheel.

5. The power distribution unit (1) according to claim 1, wherein, The cam of the switch shaft (10) presses the third contact element (6a~6g) against the spring force of the elastic element (7).

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